When padding in wind and current a skeg can be used to improve the tracking of the kayak and adjust the trim to help keep you on course. The depth of the skeg can be fine-tuned using the slider by the cockpit side.
The advantage of a skeg over a rudder is you do not have to continually apply pressure to the the steering system, however it’s not as flexible. You can swap your rudder for a skeg or have both if needed. We use a sprung skeg system with rope to control. With the rope there is less chance of a kink if you get from a jammed peddle in the skeg box, for example. Tip: Attach a small piece of string to the skeg blade so it can be easily pulled down in the event of a jam.